Objectives: The purpose of this study was to assess the protective effect of premedication and changing contrast media (CM) against repeat adverse reactions (ARs) to iodinated CM.
Methods: Between January 2006 and September 2014, 771 cases with previous ARs to CM were administered CM. The same CM that had caused ARs previously was administered to 491 cases (220 without premedication [defined as the control group], and 271 with premedication [the premedication alone group]). A different CM from the previous CM was given to 280 cases (58 without premedication [the changing CM alone group], and 222 with premedication [the premedication and changing CM group]).
Results: The control group had 61 repeat ARs (27.7%). The premedication alone group had 47 ARs (17.3%, p<0.01). The changing CM alone group had 3 ARs (5.2%, p<0.001). Three ARs (7.9%) were observed in 38 cases changing from one to another low-osmolar nonionic CM. Twenty cases with previous ARs to the high-osmolar CM and to the low-osmolar ionic CM showed no ARs. The premedication and changing CM group had 6 ARs (2.7%, p<0.001).
Conclusion: Premedication prior to contrast for patients with previous ARs may be protective, however, changing CM was more effective.
Key points: • In patients with previous adverse reactions, changing contrast media is recommended. • Premedication is unnecessary against previous reactions to high-osmolar or ionic CM. • Changing from one to another low-osmolar non-ionic CM may be effective.
Keywords: Hypersensitivity; Iodinated contrast media; Premedication; Repeat adverse reaction; Safety.